1. Field of the Invention
The claimed invention generally relates to printing and, more particularly, to a print relay system, a control method, and a storage medium.
2. Description of the Related Art
A printing system that enables a client to transmit a print instruction to a web server and causes the server to convert a target print content into print data in response to the received print instruction is conventionally known.
According to a conventional method discussed in Japanese Patent Application Laid-Open No. 2003-196054, a web server receives a print instruction and print control information from a client and the web server generates print data based on the print control information. The web server discussed in Japanese Patent Application Laid-Open No. 2003-196054 can provide a print data generation service to the client.
As described above, it is conventionally known that a web server can provide a service to a client. The cloud computing is a recently featured system that includes a web server capable of providing a service to a client. The cloud computing is mainly characterized by simultaneously processing requests from many clients using many computing resources to discretely execute data conversion and data processing. At present, many vendors are available for computer users who use web services installed on cloud computing environments that can realize such a cloud computing system capable of providing various types of services.
Google (registered trademark) is one of the noteworthy vendors that can provide numerous services on the cloud computing environments. Google has many large-scale data centers and proposes a variety of services (including print service) based on association with other devices. Google has developed an infrastructure for data communications between devices and services. For example, Google has developed a data communication infrastructure that can provide various services in association with an image forming apparatus. The interface via which an image forming apparatus can perform data communications in the cloud computing environments prepared by Google is currently opened to the public. If the above-described interface is installed on an image forming apparatus, it is unnecessary to install a printer driver on a client, similar to the method discussed in Japanese Patent Application Laid-Open No. 2003-196054.
The service that generates print data according to a print instruction from a client, i.e., a user apparatus operated by a user, is referred to as a print service. Such a service can be provided by Google. Further, a server that acquires print data from a print service and transmits the acquired print data to an image forming apparatus is referred to as a print relay system. In a printing system in which the print service is associated with the print relay system, an image forming apparatus in the intranet acquires print data across a firewall from the print relay system on the Internet or other computer network and performs printing based on the acquired print data. Therefore, a pull-type printing environment can be obtained.
As discussed in U.S. Pat. No. 7,574,545 B2, there is a conventional print technique applicable to a user apparatus, a print relay system, and an image forming apparatus to realize print processing therebetween across a firewall. According to the print technique discussed in U.S. Pat. No. 7,574,545 B2, the print relay system can instruct the image forming apparatus to perform printing based on polling from the image forming apparatus to the print relay system.
However, frequently performed polling from an image forming apparatus to a print relay system may increase the load of the print relay system. Hence, a printing system that enables each user to transmit a print instruction to an image forming apparatus via a browser installed on a user apparatus is employable. According to such a printing system, a user can send a print instruction to a print service and can send a notification including user information of the user who is communicating with the print service and print data to an image forming apparatus. Thus, the image forming apparatus can acquire print data from the print service via the print relay system at appropriate timing. As a result, it is feasible to reduce the load of the polling based print relay system.
However, sending user information and print data from a user apparatus to an image forming apparatus is troublesome for a user. For example, the following problem may arise in a printing system in which the print service manages the usage of each user for a single image forming apparatus and the print relay system manages the usage of a plurality of users for a single image forming apparatus. More specifically, each user notifies the image forming apparatus of a user whose usage is managed by the print service each time the printing is performed. When the user instruction is sent to the image forming apparatus, the print relay system can acquire print data that corresponds to the user who has instructed the printing and the image forming apparatus with which the user wants to perform printing from the print service and can transmit the acquired print data to the image forming apparatus.